Here's a hack you see in lots of erg rooms: a mirror, on wheels, that can help athletes coach themselves all winter long.

In fact, this build--The Rolling Erg Mirror--might be one of the best winter training Rowing Hacks out there, apart from the erg itself, of course.

We looked at the ways a mirror next to your erg can help you coach yourself a few years back, but we have never really had a good how-to for building one...not until UNC Head Coach Austin Work wrote to share his design a few weeks back.

Austin put his mirror together with some plywood, three eight-foot 2x4s, and some casters--and it solved a problem for the guys on the team, as he tells it.

"A few years ago, our program here at UNC had to leave a fully mirrored room in search of a new indoor training space. That new space: A squash court.

"Recently, the decision was made to finally make a rolling mirror, which has been a very nice addition to early winter training now that we're spending more time indoors.

"This thing is super easy to build if you have access to a table/circular saw and a drill," said Austin, "and it can be done cheaply."

Whether your erg room has no mirrors, or you just want to upgrade what you use now, Austin's design is very workable, and you can scale it up or down to fit the mirror you want to mount.

Lastly, the Rolling Erg Mirror also has a huge advantage over wall-mounted mirrors like the ones the UNC guys left behind: being able to wheel the mirror from erg to erg means more athletes can use it each session, and you can easily reposition it to focus on different parts of the stroke.

See below for Austin's step-by-step instructions and cut list.

Do you have a good "make the indoor training better" trick that your team uses, like, say, Handle Height Bells or the UVA Tennis Ball Trick? If so, share your ideas--and hacks--in the comments below.

If you have a great rowing hack to suggest for future inclusion, then please send it to us like Austin did and we will feature your idea in a future column.

Rolling Erg Mirror Hack How-To

Material/Price list

• Mirror - Whatever size mirror you want/need/have space for. We used a 36"x48" bathroom mirror from a recent house renovation. Found for $70 at Lowes.
• Plywood Backing/Base - Two 4'x8' sheets of ¾" plywood (you will have scraps). ($100)
• 2x4's for Frame/base - Three 8ft 2x4's will do the job. ($20)
• Fasteners - About 20 2.5 inch wood screws (~$5)
• Wheels - 4x small 2" rubber caster wheels ($5 each)
• Mirror Clips- $7
• Total Price= $222

Cut List

• Plywood
  • 1 large sheet at 38x50"
  • 2 smaller pieces at 16"x 50"
• 2x4's
  • (3x) 50" (Base and Top)
  • (3x) 9" (Interior Base)
  • (3x) 34" (Vertical supports)
  • (2x) 12" (Diagonal brace, with one end cut at a 65°)

Directions

1. Whatever size your mirror is, you will need to make the backing sheet 2" inches wider and taller. Most home improvement stores will cut whatever size you need...if, by the grace of God, the mill-saw is in working order. I swear the Home Improvement store saws and McDonalds milkshake machines are owned and operated by the same people. Because our mirror was 36x48 the final plywood back was 38" x 50" We decided on a 16x50" base for stability, but I think 12-13" would be just fine. So be sure to get two more pieces cut at that size.

2. Cut your 2x4's down to size. You can do this with a hand saw and a miter box, a miter saw, karate chops, or shape charges, but be sure you get your measurements right as we're supposed to be working with 90° angles.

3. Build your base! Attach two of the 50" 2x4's pieces, and three of the 9" (2x4's) to one of the smaller plywood sheets. Use whatever screws you have, I used 2" woodscrews. Then flip that over, and attach the other sheet on the opposite side. You'll have a "base sandwich" that looks like this:

PRO-TIP! Put small plate weights in the base for added stability! That's why I made it hollow.

4. Attach the wheels. I made the mistake of attaching these last...which is astronomically stupid for 1000 reasons. Make sure you get wheels that rotate 360° instead of the stationary variety if you want any chance to maneuver this thing between the ergs.

5. To build the vertical support, you should try to find yourself a square. Best to attach the vertical pieces to the base first. While I used a pocket-hole jig, you can easily "toe-nail" screw the verticals to the base. See photo of the pocket holes below. Find dead center on the ends of the base, then use your square to make sure the vertical 2x4's are as close to 90° as they can be.

6. Attach the top brace to the top of the three vertical boards. Again, use your square to make sure all three connections are at 90°.

7. Now for those little diagonal support pieces. Originally I didn't think I needed them because it felt really stable. Then I realized that people were likely going to move the mirror around by pushing/pulling the top of the mirror, which could easily loosen it from the base over time. While these were initially just insurance, as soon as I installed them I realized what a difference they made. You can cut the bottom piece to whatever angle you want. I went with 65° on my miter saw, but you can use a miter box and hand saw if you don't have anything else.

8. Attach the Large piece of plywood to both the base and the top brace. I angled it back about 8-10° (so people erging could see themselves) then used wood screws to attach it to both the base and upper 2x4.

9. Screw 4 mirror clips on the bottom of the plywood (all at an equal height from the base) and carefully insert and lean the mirror against the plywood. Attach the rest of the clips wherever you see fit. I think I used 8 total clips (1 package).

And there you have the Rolling Erg Mirror!